First Family Project - Plywood Hovercraft

[Rob Will]

Looking for a way to get the kids to clean up all the dust from the shop floor??? This might be just what you need........

It's not what one would call "fine woodworking" but I did get an opportunity to make a first wood shop project with the girls. They had a blast.

During the course of thinking about air bearings to float the Moak 36, we got to talking about Hovercrafts and how they work. (Years ago we made one from an old grain bin fan and the 8 horse Briggs from Dad's Snapper.....err...that worked, but didn't go over too good).

This afternoon, the girls and I went out to the new wood shop and we made a Hovercraft out of 3/8" plywood and a Shop Vac (removable) leaf blower. The bottom skirt is 6 mil plastic. (do a Google search for "Human Hockey Puck")

This thing has so much lift that the whole family can stand on it. We actually had to duct tape the blower inlet to tone it down a bit. I'm thinking about putting a tee in the blower port and going through the box seat and out the rear for a jet exhaust (for forward propulsion) and to bypass some of the excess air.

Anyway.....I'm grinning from ear to ear......I built this new shop to do projects with the kids..... and from the look on thier faces:) , they'll be back for more!

Rob

[Gary Herrmann]

First of all, your girls are very cute.

Second of all, I have got to build one of those for my son!

[Jim Dunn]

Great idea. When my granddaughter weights enough to ride one I'll have to build one for her. Thanks for the idea. Oh yeah, your girls are too cute:)

[John Schreiber]

You're gonna get dad of the year. They won't forget that ride.

[Brad Trent]

Made one a few years back with some Cub Scouts -- you get both woodworking and science all in one session We did some Scout bowling on the these, trying to see who could knock down the most boxes. I still get calls occasionally from other groups that want to learn more.

[Bruce Page]

Way cool! The girls will be smiling in their sleep!;)

[Rob Will]

Some materials that might come in handy......

A 2-hole conduit clamp that fit the pipe on the leaf blower sure came in handy to strap it to the seat.
A Hole saw same size as the leaf blower to make a tight fitting hole through the plywood. Don't let the blower protrude through the bottom.
1 Box of 100 #6 x 5/8" countersunk wood screws to fasten the two pieces of plywood together - mostly around the perimeter.
A roll of tape to wrap the edge of the lower plywood disc to help protect the plastic sheeting. Also can tape down the edge of the plastic where you staple it for a better seal.
Some 1/4" or 5/16" staples to fasten the plastic.
A small roundover bit to run the edges of everything.
A sharpened piece of pipe or conduit to punch vent holes in the plastic sheeting. (1-1/2" to 2" ?)
It is worth noting that the bottom plywood disc is 1" smaller dia than the top disc. This gives you a bumper all the way around to help protect the plastic sheeting from damage.

Hope you have some fun with this......but you'll have to let the kids ride too!

Rob

[Robert Mahon]

Makes me wish my kids were still young and living near me. Da*n, where was my sense back then? :confused:

What a great idea.........good for you.

Ever think about a 2nd directional blower for propulsion? Locate the elevating blower under the vented seat and use the other to direct which way you want to go. When going forward you can also air-brush your hair (I'd be more streamlined).

BTW, get some really, REALLY long HD extension cords.

Seriously, that was a great idea.

[Jim Becker]

I am thinking that your investigation of pneumatic mobility has led to more fun things.

Now, what you need to add to that is a way to use the "extra" air to provide directionality... :D

[Jim McCarty]

I'm thinking that my Echo gas blower would give even more power AND unlimited range. Of course, I might never see the kids again.

[Robert Mahon]

Of course if you do this, you'll have to take a "Test ride" to make sure all's well.

In that case, they may never you again.

Who-eeee, what a ride.

[Jon Shively]

Thanks for the great idea. Have bookmarked this, my one daughter thinks this will be the best wood craft or recycling project she has ever made! Daughter's smiles are genuine, good job there dad!! By the way, you do know you now have to go buy a new blower, that one is a dedicated hover craft engine.

[Frank Lopez]

Now you got my little pea brain buzzing. Here's a possible "upgrade". If you place the blower on a tee like you suggested, in the seat box and exhause it out the back, you'd get forward propulsion. Now put the box/seat/blower assemly on a lazy susan type swivel, you'd be able to steer that bad boy.

Get rid of the electric blower cord an go with a small gas power or a DC voltage converable with a battery and you might have to get in the car to chase 'em down and bring 'em back home.

I think I'm gonna build one for me. And another just for moving heavy stuff around in the shop and garage.

[Larry Fox]

YES!!!! I think this is my next project. Any idea if it would work on asphalt? I have a large driveway and my sons would have a hoot on that thing there.

Over the weekend I had them on one of those metal dishes sold for sleding. I attached a short dog lead to it and would stand in one spot and spin them around to get up speed and release them down the driveway (think the motion a shot-puter uses only the sled never leaves the ground). This was sooooo much fun for them (driveway is 1/10th of a mile long so no chance of them ending up in the street). Point being, if they liked a sled that much I will will dad of the century for this one.

Muhahahah

[Roy Wall]

Rob - great post!!!

Like Larry Fox - can it get off smooth concrete? ..at least the rough finished concrete on the driveway??

[David Cramer]

Excellent Rob!!!! What a cool idea and now a future Cramer project! My 7 year old would get a real kick out of it, as would I:D . Thanks for the photos and details of how you built it. Hover on!

Dave

[John Gornall]

I think I see the idea for a mobile base for my UNI!

And maybe my workbench.

[Travis Hirst]

That is awesome!!!! My five year old would live that. Could you be a little more detailed in how you use and install the plastic. I have never built one of these but I think that would be a great project for the kids and I this summer. Thanks

Travis

[Jim Dunn]

After reviewing the plans on the "human hockey puck" page I have more questions than answers. First: What are the air holes in the bottom piece of plywood for? 2nd: Are the holes through the plastic?

Seems I just can't get it straight in my befuddled head.:)

[Frank Chaffee]

Rob,
What a terrific project to share with your kids! Heck, the smile on my face right now rivals those of your daughters. :D :D

How about this: A back mounted blower with supply air to two foot pads that would allow one to “skate” forward. The pads narrower than snowshoes and shorter than skis. A valve in each supply line that closed when air flow became too great, i.e. when one foot was lifted.:eek:

Frank:)

[Ron Wessels]

My reading is that the holes are not in the bottom piece of plywood. They are in the plastic that totally covers the bottom of the bottom piece of plywood.

I would doubt that this would work on any "rough" surface like asphalt or rough concrete. It would simply rip the plastic on the bottom.

[Jerry Strojny]

Rob,

Very cool, very fun. I am putting this in my "eventually to do" list. Isn't it just great when everyone gets involved? (Mythbusters did something similar...great stuff)

[Travis Lavallee]

I have seen a few of these built before. The next step is the gas powered leaf blower for the hover aspect. After that you add a small motor, such as one from a line trimmer with a propeller on it. You can then add rudder like panels to it with levers and cables to control the steering. Then see what kind of trouble "your kids", ie. you and kids, can get into with it.

[Rob Will]

Thanks guys!:) Here's a few more details:

Will it go on concrete or asphalt? The best performance will be on a smooth, sealed floor. With a enough horsepower (gasoline blower?) it should work on slightly rough surfaces. The biggest problem that I see is with rough surfaces damaging the plastic sheeting.....perhaps there is something better than plastic(?).

Here's the general idea of constructing one of these hovercrafts:
From one sheet of 3/8" (decent grade) plywood cut two circles - one 48" and the other 47". The small disc goes on the bottom. The larger disc forms a "bumper edge" overhanging the top. The plastic sheeting forms a inflatable seal that conforms to the ground conditions.

Layout:
This would be a good time to figure out where you want to position the blower and seat. I placed a broom handle side to side under the plywood as a temporary balance point and had my oldest daughter sit on the unattached seat assembly. We shifted things fore and aft a little bit to obtain the best comfort and balance. This was not really that critical so just make it comfortable. A seat that is long front to back helps to get the blower away from you and also provides something to attach the blower to. Once you have determined where the blower will go, clamp the sheets together and bore a hole for the leaf blower. Do not allow the leaf blower to protrude all the way through the plywood.

Plastic Sheeting:
On a smooth, clean table, lay out a piece of plastic (I used 6 mil).
Place the smaller plywood disc (with taped edge) on the plastic sheeting.
Without stretching the plastic tight, fold the edges up onto the plywood and staple - about 1-1/2" in from the edge.
Cut off the excess plastic and apply duct tape to seal the edge.

Seat attachment:
You might want to affix some cleats to attach the seat to on the larger disc before you put the two discs together.

Joining the two discs:
Place the larger plywood circle on top of where you just applied the staples and tape. Center it over the smaller circle and fasten together with a bunch of 5/8" screws - mostly around the perimeter. Push them together tightly when screwing......to obtain a better seal.

Install the lower strain relief:
Cut a small (8"?) circle of plywood and round the edges. Flip the hovercraft over and screw the small disc right in the center over the plastic. Use about 8 - 1"screws. This plywood disc forces the plastic sheeting to form a donut shape when inflated.

Cut the vent holes in the plastic:
Using a sharpened piece of 1-1/2" - 2" conduit or some other hole punch, make a series of holes in the plastic around the lower strain relief. Leave enough material to keep the plastic strong. Do not punch any holes toward the outer edge, keep them in toward the center 1/3.

If in doubt, search for "human hockey puck".

Rob

[Jason Tuinstra]

Very, very cool! I can see this being the neighborhood attraction.

[Randal Stevenson]

My appologies for the loss of your shop, through the girls hockey years. Just watch out for them trying to high stick you, when you want to get some work done.









Really cool, just gotta make sure the nieces and nephews NEVER see that.

[Rob Will]

After reviewing the plans on the "human hockey puck" page I have more questions than answers. First: What are the air holes in the bottom piece of plywood for? 2nd: Are the holes through the plastic?

Seems I just can't get it straight in my befuddled head.:)

Jim,
There is only one hole in both sheets of plywood, that is where the leaf blower forces air all the way through. These holes (2-1/4" or so) line up with each other and that is where the blower goes. The only real reason that there are two sheets of plywood is to make it easier to seal the edge of the plastic skirt.

The plastic completely covers the bottom disc but the plastic has some vent holes of it's own.

The air comes through the plywood sheets and softly inflates the sheet of plastic.

The plastic is what you might call "semi-inflated". It only holds enough pressure to conform itself to the floor surface thereby creating a seal.

Air escaping out of the vent holes in the plastic is what pressurizes the entire area below and provides lift.

For what it's worth - two men totaling 485 lbs moved around on my smooth shop floor with this hovercraft today.

Rob